Grease gun



Nov. 5, 1940.

Filed March 24, 1959 3 Sheets-Sheet 1 um, Nm, I g l1 I I n@ l NM Sm, MM,

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N. V. SMITH Nov. 5, 1940.

GREASE GUN Filed March 24,V 1939 3 Sheets-Sheet 2 N. V. SMITH GREASE GUN 3 Sheets-Sheet 3 Filed March 24, 1939 H f M 7//// f .NN mw Q m5 6 Nw f Hf d MMI-.- -lill i Q Q90 wm wh QQ R n uw" MV. Y v N\ V// wv .NNLMMMW Patented Nov. 5, 1940 UNITED STATESA PATENT ori-fica GREASE GUN v Neil V. Smith, Los Angeles, Calif. n applicati@ March 24, 1939, seal No. 263,969 l if 13 Claims.

This invention relates to a lubricating device and relates more particularly to a grease gun for discharging grease and other lubricants into bearings, etc., under pressure. A general object of this invention is to provide a practical, effective grease gun embodying a novel charging or priming means.

The hand operated grease guns that have been introduced usually embody a cylinder and ram m: mechanism for discharging the grease under pressure when a manual thrust is applied to the device, and a charging or priming means for supplying charges of lubricant to the cylinder and ram ejecting mechanism. The lubricant or l5 grease oiiers substantialresistance to flow, particularly where heavy bodied lubricants are handled, and the priming means must be capable of moving a full charge of the lubricant into the cylinder before the ejecting ram begins its 20 next ejecting stroke. In the grease guns that have gone into general use it has been customary to employ as a priming means a piston or follower behind the supply of grease and to urge the follower against the grease either by air under g5 superatmospheric pressure or by a spring. The

' air under superatmospheric pressure, or the spring acting on the follower, forces the charges of lubricant or grease into the ejecting cylinder. When air pressure is thus utilized to charge 301 the ejecting means, the pressure decreases as the operations continue, unless renewed from time to time, and the grease gun construction must be large and expensive to handle and retain a suicient supply of the priming air. Where a spring 3,-)- is utilized to charge or prime the ejecting means, the priming force decreases as the operations progress and a substantial space must be provided in the grease gun barrel to contain the priming spring.

4 The high pressure cylinder or ejecting cylinder of a hand operated grease gun must be quite small in diameter, and of substantial length, to provide easy manual operation while developing the required discharge pressure and capacity.

45 Prior attempts to utilize atmospheric pressure as a priming or charging force for such a gun have not proved entirely successful, as this force alone is insufficient to overcome the frictional resistance to the iiow 0f heavy lubricant into a pas- 50' sageway of this nature and thereby charge the ejecting cylinder at the required operating rate.

An object of this invention is to provide a grease gun having a charging means or priming means operable to supply or introduce a full 55,- charge of lubricant toathehigh pressure cylinder for each discharge operation without necessitating the fuse of superatmospheric pressure or yspring pressure.

' Anothenobject of ,this invention is to provide a grease gun in which atmospheric pressure is utilized to fo-rce or feed a charge of lubricant to a primary cylinder for subsequent transfer into the ej'ecting cylinder yor 'high pressure cylinder. The atmospheric pressure employed as a charging force in the device of the present invenl0 tion is constant, uniform, always available and inexpensively utilized, as distinguished from those methods employing varying or lessening spring pressure, or lessening superatmosph'eric pressure requiring special and expensive construction fea- 15 tures.

Another object of this invention is to provide a grease gun in which the high pressure cylinder or ejecting cylinder is charged or primed during the discharge stroke or forward stroke so that full actuating force, of say 60 pounds, is available .to charge the cylinder.

Anotherobject of this invention is to provide a grease gun of the character mentioned in which the priming cylinder -is larger in diameter and at least equal incapacity to the high pressure cylinder, and in full communication with the lubricant supplyduring the charging period, so that a full charge of lubricant may be quickly supplied to it with a minimum of frictional resistance.

Another object ofthis linvention is to provide a grease gun involving axially aligned and directly communicating cylinders for priming and high pressure ejecting functions, and pistons or 35 rams for the cylinders arranged in telescopic relation and releasably held against relative movement during an initial portion'of the forward stroke, or until the charge of lubricant has been displaced from the priming cylinder to the high pressure cylinder by" the priming ram, following which an independent action of the forwardly vmoving high pressure ram forces a-full charge of lubricant yfrom the high pressure cylinder under substantial pressure.

Another object of this'invention is to provide a grease gun of the character mentioned in which the charging ram restores or leaves the charging cylinder before the :high pressure ram leavesr its cylinder, thereby providing an ample time interval for the priming lubricant charge to occupy the charging cylinder before the succeeding forward stroke is initiated. k

Another object of this invention isl to provide a grease gun of the character mentioned embodyand applications of the invention, throughoutJr ing means for immediately returning the priming ram or charging ram at the completion of its forward stroke, thereby providing a maximum time interval for the charging of the priming cylinder.

Another object of this invention is to provide a grease gun of the character mentioned embodying novel latch means or detent means controlling relative movement between the rams.

A further object of this invention is to Aprovide a grease gun that is operable to contain a maximum supply of lubricant for a given over-all size. The various objects :and features of my invention will be fully understood from the following detailed description of typical preferred forms which description reference is made to the accompanying drawings, in which:

Fig. 1 is a central longitudinal detailed sectional view of one form of device of the invention with the lparts in the idle positions and showing the inner ram and the actuating stem in elevation. Fig. 2 is an enlarged fragmentary longitudinal detailed sectional 'view of the forward portion of the gun illustrated in Fig. 1 showing the rams in forward positions. Figs. 3, 4 and 5 are enlarged transverse detailed sectional views taken as indicated by lines '3-3, 4`-4, and 5 5, respectively, on Fig. 1. Fig. 6. is a central longitudinal detailed sectional view of another form of the invention -withk the parts in the normal positions and showing the high pressure ram and the actuating means in elevation. Fig. '7 is an enlarged longitudinal detailed sectionalview of the principal parts of the device illustrated in Fig. 6 with the rams related to initiate return movement of the priming ram. Figs. 8 and 9 are enlarged transverse detailed sectional views taken as indicated by lines 8-8 and 9 9, respectively, on Fig. 7. Fig. 10 is a central longitudinal detailed sectional view of another device of the invention with the parts in the unactuated positions, showing the high pressure ram and the actuating means in elevation. Fig. 11 is an enlarg-ed longitudinal detailed sectional'view of the intermediate portion of the gun illustrated in Fig. 10 showing the high pressure ram at the forward end of its stroke and the charging ram restored and Fig. 12 is an enlargedftransverse detailed sectional view taken as indicatedby line I2-I2 on Fig. 11.

Figs. 1 to 4, inclusive, illustrate a form of the invention that may be said to comprise, gener-ally, a body I0 for containing a supply of lubricant subjected to the action of atmospheric pressure, a head Il on the forward end of the body -II) having a charging cylinder or priming cylinder I2 in receiving relation to the lubricant supply, and an ejecting cylinder or high pressure cylinder I3 in receiving relation to the cylinder I2, rams I4 and I5 operable in the cylinders I2 and I3, respectively, and operating and control means IB for the rams I4 and I5.

The body I0 is provided to store or contain a supply of the lubricant and to support the various other elements of the device.` The body I0 may be an elongate, generally' cylindrical member closed at its rear end by a threaded-on cap I1. It is a feature of the invention that the supply of lubricant may occupy substantially the entire interior of the body I0 and that the lubricant is urged forwardly in the body by atmospheric pressure to flow lor feed into the priming cylinder I2. It is preferred to provide a piston or follower Fin the body I0 behind the body or supply'of lubricant to be acted on by the atmospheric pressure. The follower F may be of -any selected construction. In the case illustrated the follower F includes a resilent sealing ring I8 held between metal rings I9. The ring I8 slidably seals with the interal wall of the body IIJ and seals with a central longitudinal part associated with the ram I4 as will be subsequently described. The cap I1 may be ported as at 20 to freely admit atmospheric pressure to act on the rear side of the follower F.

The head I I is removably secured to the forward end of the body Ill and projects forwardly from the body. An annular apron or flange 2| on the rear end of the head II is threaded on the forward portion of the body IB. A rearwardly facing sealing gasket 22 is set in a groove in the head II and seals with an inturned part 23 on the forward end of the body II) to prevent the leakage of the lubricant from between the body and head. The forward portion 24 of the head II is elongate and is reduced in diameter and is connected with the flange 2| by -a tapered portion 25. The tapered portion 25 of the head II has an internal cavity or chamber 26 in full communication with the forward end of the body I0.

The communicating charging or priming cylinder I2 and high pressure or ejecting cylinder I3 are formed or provided in the head I I. In accordance with the invention the charging or priming cylinder I2 has direct full communication with the lubricant supply in the chamber 26 and the body I0. The cylinder I2 is concentric with the` longitudinal axis of the head II and its rear end isin direct communication with the chamber 26. As illustrated, the' cylinder I2 may be in the nature of a rather shallow socket of substantial diameter. A plurality of circumferentially spaced ribs 21 is provided on the interior of the head I I. 'I'he ribs 21 extend rearwardly from the cylinder I2 to center and guide the ram I4. The ejecting cylinder or high pressure cylinder I3 extends forwardly in the head II from the forward enc'. of the priming cylinder I2. In the preferred construction the cylinder I3 is quite long and small in diameter to provide for the easy manual operation of the device. The cylinders I2 and I3 are related so that the capacity of the priming cylinder I2 is at least as great as the capacity of the ejecting or 4high pressure cylinder I3. The cylinders I2 and I3 are co-axial or in concentric relation and their walls are machin-ed or finished.

A discharge passage 28 extends longitudinally through the forward reduced head portion 24 to conduct the ejected lubricant to a discharge nozzle 29. A coupling or adapter 30 may serve to connect the nozzle 29 with the forward end of the head portion 24. An opening 3| of reduced diameter connects the forward end of the cylinder I3 with the discharge passage 28. A valve 32 seats inwardly or rearwardly against the restriction provided by the opening 3l and is urged to its closed position by a spring 33. The spring 33 may be arranged under compression between the adapter 30 and the valve 32 and is sufficiently strong to hold the valve closedto prevent a reverse or return fiow of air and/or lubricant and to prevent the bleeding of the lubricant from the gun. The forward or outer part of the valve 32 is slotted and provided with a longitudinal opening 34 to permit the free discharge of the lubricant.

The rams I4 and I5 are operable in the cylinders I2 and I3, respectively, and are related for zazae'ov" relative longitudinal movement;Y VAs illustrated in the drawings the rams I4 and I5 arel tele-` tubular cylindrical memberg'and the ram I5- isv the inner ram, being an elongate rod-like part extending through the outer ram I4. Theouter ram I4 is proportioned to accurately fit the charging or' priming cylinder I2 with working clearance while theram I5 accurately fits the high pressure cylinder I3 with? mechanical or working clearance. The inner ram I5 extends completely through the outer'ram I4 and isof sufficient length to have full movement in the cylinder I3 when the ram I4 is in its forward position in theV cylinder I2. A tube 36 is threadedly connected with the rear end of the ram I4 and extends rearwardly inthe body Ill. The follower F surrounds and moves along the tube 36. The sealing ring I8 of the follower F has active sealing engagement with the tube 36. A packing assembly 31 is arranged between an internal shoulder 38 on the tube 36 and the rear end of the ram I4 andseals about the high` ing of the priming cylinder I2, the charging of the high pressure cylinder I3and vthe ejection of the charge fromthe high pressure cylinder I3' with theseoperations taking place in the order named.v The means I6 is manually actuated and comprises an operating stem 39 connected to the high pressure ram I5 and an operating handle 4U on the stem 39. The stem 39 may be a rearwardly extending continuation of the ram I5 and passes rearwardly through the tube 36. operating stem 39 extends through a tubular bushing or nut4I carried by the cap vI1 and its projecting rear part carries the handle 4I).V The nut 4I is removably threaded in an opening 42 in the cap I1 and its` accessible rear part is knurled for ready turning. The handle 49 may be asuitable pistol grip. It will be seen that the handle 40 may be operated to directly manually reciprocate the high p ressure ram I5 relative to the bodyv I0. In the construction illustrated the forward part ofthe operating *stem 39 is of enlarged diameter toprovide a rear-` wardly facing annular shoulder 44. A tubular nut orY bushing is threaded in the rear end o-f the'tube 36 and the shoulder 44 is engageable with the'nut 45 lto limit the rearward travel of the ram I5 relativeto the ram I4; although this for causing movement of the charging ram I4 with the high pressure ram I5 during a phase'or portion of the forward stroke of the ram I5, and during a phase or portion ofthe return stroke of the ram I5. This detent mechanism includes' an annular groove 41 inthe high pressure ram I5. 'Ihe groove 41 is spaced rearwardly from y*the forward end of the ra'm'l I5'.-- Spring urged The elements on the ram I4 cooperatewith the groove 41 to relea'sably connect the rar'ns I4 and' I5 for concerted movement. `These elementsl may be in the nature of balls 4'8 rshiftable in radial openings 49 in the ram I4. The balls 48` are adapted-to project from the inner ends of the openings 49 to cooperate with thegroove 41 and shiftable followers or blocks 50 may be arranged in the openings 49 to bear inwardly against the outer sides of the balls 48.- An annular flange 5I is provided on the ram I 4` in surrounding relation to the series of openings 49 and has a peripheral annular groove v52. 53 is arranged in the groove 52 to urge the blocks 50 and the balls 48-'inwardly'.l The spring 53 may be a straight helical spring shaped to constitute a ring and has its ends hooked together o-r otherwise connected. The outer faces of the blocks 50 are shaped to substantiallyconforn to the spring 53. The groove 41 is o-f'substa'ntial tensive cooperation with kthe'groove 41 so that a substantial force' is' required to unseat the balls from the groove `41 against the action of the spring 53. The spring 53 of course may'b'e designed to'urgefthe balls'48 inwardly with any selected force.

The parts are proportioned and related so that the forward ends ofthe rams `I4` and I5 are substantially flush when the balls 48 are in cooperation with the groove 41; vThe two rams are in` thisrelation at the beginning of the forward stroke. During'the forward stroke of the operating stem 39 the rams I4 and I5 move together or as a unit until the ram I4 reachesY the end4 the raml I5` continues vforwardly inits cylinder I3 while the 4ram I4`rem'ains" stationary. The concerted forward movementV ofV the two rams I4 and I5 causes the positive displacement of the charge of lubricant from the cylinder I2 -to the cylinder I3 and the subsequent independent movement of the ram I5l ycauses the 'positive high pressure displacement of the lubricant charge from the cylinder I3 through the opening 3l and passage 28 tothe nozzle 29.

' Upon'the return strokethe ram I5 moves rearwardly'relative tothe ram- I4 until the groove 41 reaches the series of ballsv 48'. The balls 48 enter' the groove 41 under the action of 'the spring 53and serve to connect the ram I4 with the ram I5 to move rearwardly with the ram I5.`

Thus during the second or nal portion of the return stroke the rams I4 and I5'move together as a unit to the position' illustrated in Fig, 1. During this phase" of the return stroke a sub stantial reductionA in pressure is created in the communicating cylinders I2 and I3 and when the ram I 4Y leaves thelcylinder I2 the lubricant under atmosphericvpressre quickly flows into the cylinder I2. The lubricant-,under the action of the atmospheric pressure o'n the follower F completely occupies the priming cylinder I2 and may partially nll the cylinder I3. The lubricant under atmospheric pressure readily ows into the large diametered .cylinder I2 which hasl full communication with the lubricant supply. Thus the priming cylinder I2 is primed orrprovidedy with a charge during the return stroke and thisl charge'is displaced from the ycylinder I2`to the cylinder I3'during the first phaseof theforward A helical spring 2lidepth and the spring urged balls`48 have ex` stroke. .As above described, the capacity of the cylinder I2 at least equals the capacity of the cylinder I3 and the displacementl of the charge from the cylinder I2 to the cylinder I3 by the above-described concerted forward movement of the two rams `I4 and I5 assures the complete,

positive priming or charging of the cylinder I3.

The charging of thelarge diameter-ed cylinder I2 is rapid and complete, and the charging of the cylinder I3 is complete and positive. It will be understood how the balls 48 freely ride on the cylindrical surface of the ram I5 during movement of the ram relative to the ram I4. The balls 48 under the action-of the spring 53-enter the groove 41 to assure the positive return movement ofthe ram I4 with the ram I5 during the final portion of the return stroke. It will be observed that the return stroke is accompanied bya substantial evacuation action which assures the full charging of the priming cylinder I2 by the lubricant under atmospheric pressure.

The above operations may be repeated until the supply of lubricant in the body I8 is depleted. When this occurs the head II is unthreaded from the body I and the forward portion of the body is introduced into a supply of the lubricant. The nut 4| is unthreaded from the cap I1 and the stem 38 is moved rearwardly. The resultant rearward movement of the tube 36 and ram I4 is transmitted to the follower F by the engagementof the flange I with the follower, and the rearwardly 'moving follower draws a replacement lcharge of lubricant into the body I8. 'I'he head I I is then replaced and the nut 4I threaded into its opening 42 to put the device in condition for further use.

The form of the invention illustrated in Figs. 6to 9, inclusive, of the drawings may be said to comprise, generally, a body I8 for containing a supply of lubricant under atmospheric pressure, a head II on the forward end of the body I0 having a priming cylinder I2, and an ejecting or high pressure cylinder I3, rams |41 and |51 operable in the cylinders I2 and I3, respectively, and control and operating means |61 for `the rams |41 and |51. The body |0, the head II and the follower F of the structure illustrated in Figs. 6 to 9, inclusive, may be the same as in the preceding form of the invention.

The ram |41 is substantially the same as the ""ram I4, being a cylindrical `tubular member decylinder I3.

signed for operation in the -charging cylinder or priming cylinder I2. A tube 361 is threaded on the rear portion of the ram |41 and extends rearwardly through the body. In this construction lthe tube 361 may have its forward end bearing against an annular ange 60 on the ram I 41. The ram |51 is similar to the ram I5, being a simple cylindrical element of uniform diameter operable in the high pressure cylinder or ejecting The ram |51 extends completely through the ram |41 and its rear portion projects into the tube 361. A packing assembly 6I may be arranged between an internal shoulder 62 on the tube 361 and the rear end of the ram |41 to provide a lubricant tight seal about the ram |51.

The control and operating means |61 is manually operable to reciprocate the rams |41 and |51 in their cylinders I2 and I3 in a given relation or in a special manner to provide for the displacement of the lubricant `charge from the cylinder I2 to the cylinder I3 and the displacement or ejection of the charge from the cylinder I3 during the forward stroke, and to provide for .,theinitiation of the priming or charging of the stroke.

The means 61 includes a stem 63 resembling the above described stem 39 and vconnected withA or forming a continuationof the high pressure ram |51. The operating stem 63 extends rearwardly through the tube 3611 and passes through the nut 4I to project from the rear end of the cap I1.l A suitable pistol grip handle 48 may be fixed to the rear end of the stem 63. The ram |51 is, of course, directly manually operated by operation of the handle 48.

The means |61 further includes a novel latch means or detent means for connecting the ram |41 with the ram |51 during certain phases of the operation. In this form of the inventionythe detent. means is provided in the rear portion of the device and includes two longitudinally spaced annular grooves 64 and 65 in the operating stem The front groove 64 is spaced rearwardlyy An extenplurality of spaced radial openings 61 is provided,

in the section 66 and balls 68 are contained in the openings 61 to cooperate with the grooves 64 and 65. Longitudinal grooves 69 are provided in the section 66 and extend rearwardlyfrom the openings 61 and leaf springs 18 extend through the grooves 69 to cooperate with the balls 68. The springs 10 serve to urge the balls 68 inwardly to have the desired cooperation with the grooves 64 and 65. A cap 1I is force-fitted over the rear end of the section 66 and overlies the springs 10 to urge thesprings inwardly against the balls 68 and to hold the springs in place. 'I'he rear end portions ofthe springs 10 may be gripped or clamped between the end of the section 66 and the cap 1I tov assure the proper retention of the springs. The springs 18 are yieldable to allow the balls 68 to move outwardly from the grooves 64 and 65 when there is a given resistance to movement of the ram |411 withthe-ram |51. .l

The parts are related so that the. forward ends of the rams. |41 and I5*1 are in substantially the same plane when the balls 68 are in latched engagenient with the front groove 64.and so that the ram |51 projects forwardly from the ram |41 a distance substantially equal to the length of the cylinder I3 when the balls 68 cooperate with the rear groove 65. The --cooperation of the-ram |41 with the forward wall of the cylinder I2, or with the lubricant in the cylinder I2, is adapted to limit the forward stroke of the ram, while the cov operation of the cap 1I with the nut 4I .may limit the rearward stroke of the ram |41. The engagement of the handle shank 46 with the nut 4| may limit the forward movement of the ram |51 and the cooperation of the shoulder 441 with the section 66 may limit the rear movement of the ram-y |51 with respect to the ram I 41. The shoulder 441 is adjacent to or in cooperation with the forward end of the section 66 when thefballs 68 are in latching cooperation with the front groove 64.

In operating the grease gun illustrated in Figs. 6 to 9 the nozzle 29 is suitably engaged with the fitting to receive the lubricant and the handle 48 is reciprocated to effect the ejection of charges of lubricant into the fitting. At the start of the forward stroke the parts are in the positions illustrated in Fig. 6 with theballs 68 engaging in the front groove 64. The balls 68 cooperating with the front groove 64 cause the arm |41 to travel forwardly gr/ith theramkvi 51-to displace the charge? of lubricant from the cylinder IZ-intothe cylinder I3. The ram I4a continues to move forwardly to the end of its stroke or until the resistance to itsforward movement becomes so great that it overcomes the latching yengagement of the spring urged balls 68 with the groove 64. The ram I5a continues to move forwardly to enter the cylinder I3 and the forward groove 64 moves out ofcooperation with the balls 68. Theram I5El moves forwardly through the cylinder I3 to eject the charge of lubricant through the passage 28 and the nozzle 29 under a substantial pressure. In this connection it is to beobserved that the lubricant is ejected from the cylinder I3 by the direct manual thrust without resistance offered by a return spring, or the like. l y

The high pressure ram I5a moves forwardly to the end of its forward stroke and upon or during its return stroke the rear groove 65 engages or receives the spring urged balls 6 8. The engagement of the ball-s 68 in the groove 65 connects the ram I4a with the ram I5a to return with the rain I5a during the return stroke of the same. The low pressure ram or priming ram I4a moves rearwardly with the ram I5a to leave the cylinder I2 and continues moving rearwardly until the cap 1I engages the nut 4I. This engagement of course stops the rearward travel of the ram I4aL and the groove 65 moves rearwardly out of cooperation with the balls 68. The return movement of the ram I4EL just described takes place during the initial phase of the return stroke of the ram I5a and is completed while the ram I5 is still in its cylinder I3. When the ram I4il leaves its cylinder I2 the lubricant from the main lubricant supply immediately enters or fills in the cylinder I2 under the action of the atmospheric pressure working against the follower F. 'Ihe lubricant may continue to flow into the cylinder I2 during the remaining phase of return movement of the ram I5a. The ram I5a continues its rearward travel to the end of its return stroke, at which time the front groove 64 comes into position to receive the balls 68. This reconnects the ram I4a with the ram |59' for the next ejecting stroke.

The operation of the grease gun illustrated in Figs. 6 to 9 is characterized by the fact that the lubricant has a substantialtime interval to fill or occupy the priming cylinder I2 before the for- Ward stroke is initiated. The ram |4a. leaves the cylinder I2 during the initial phase of the return stroke leaving a substantial period of time forthe cylinder to ll with a charge of lubricant. Thus the full charging of the ejecting mechanism is assured. It is to be noted that the grooves 64 and 65 of 'the latch mechanism or detent mechanism may be formed in a portion of the ram and stem structure that is of substantial diameter. With this location of the grooves the grooves do not tend to weaken the structure. The body IIJ may be filled with lubricant from time to time as described above in connection with the preceding form of the invention.

The embodiment of the invention illustrated in Figs. 10, 11 and 12 may be said to comprise, generally, a body I0, a head II on the body I6 having concentric cylinders I2 and I3, rams I4 and I5 operable in the cylinders I2 and I3, and con.- trol and operating means I6'D for the rams. The construction illustrated in Figs. 10, 11 and 12-:may be identical with that shown invFigs. 1 to 5, inclusive, with the exception of certain element-s of the means I6b and corresponding reference lnected with thestem 39h.

numerals designate corresponding parts of the two embodiments of the invention. I

The control and operating means I6b includes an operating stem 39h, connected with or forming Aa rearward extension of the ejecting ram I5 and extending Vrearwardly through the tube 36 and the nut 4I to carry the operating handle 40. The means I6b further includes the groove -41 in the ramv I5, the balls 48 and the blocks 58 in the openings 49, andthe spring 53 urging the blocks 56 and the balls 48 inwardly so that the balls cooperate with thel groove 41, all as .described above. In this form of the invention the control and operating means I6b operates to automatically return the charging o-r priming ram I4 to its rearmost position at the completion of its forward stroketo-provide for the charging orfilling ofthe cylinder I2-during theactive forward stroke of the ram I5. f `The means I6b is characterized by a power vmeans or spring means for restoring or returning the ram I4. The spring return means comprises a springll connected with the ram I4 and connectedswith the operating stem 39h. The spring 80is preferably in the form of a helical extensible tension spring arranged in the `tube 36 in surrounding relation to the plunger I5. The forward end of the spring 86 is connected with the ram I 4 and the rear end of the spring is con- In the construction :illustrated Lthe forward end part of the spring 8|! extends .through an opening 8I in a washer 82 of the packing assembly 38 and has an ear or lug 83 turned down to bear against the forward face of the Washer and the rear end of the spring 88 has a linger` or lug 84 set in a socket 85 in the stem '39b and retained in the socket by the surrounding and confining tube 36. The spring 80 is under, tension to urge'the ram I4 rearwardly relative to the ram I5. j The engagement of the bushing 45' with the lnut 4I limits the rearward movement ofthe ram lI 4 and the parts are related so that the balls 48 cooperatewith the groove 41 When-the two rams I4 and I5 are in their rearmost positions. The spring 80 is of such strength that it does not overcome the holding or retraining cooperation of the balls 48 with the groove 41. However, upon the release of the balls 48 from the groove 41 the spring 80 quickly returns the rarn ,I,4.to its rearmost position and this action vtakes place during forward movement of the ram I5. 5

In the operation of the grease gun illustrated in Figs.f l.11 and S12 the nozzle 29 is engaged against or connected with a lubricant receiving fitting and the pistol grip or handle 40 is reciprocated to operate the gun. During'the forward stroke the balls48 cooperating with the groove 41 connectthe ram rI4 with the ram I5 so that the two ramsmove forwardly together. The two rams enter the cylinder I2 and displace the charge of lubricant from this cylinder to the cylinder I3. This supplies a full charge of lubricant to the :ejecting cylinder or high pressure cylinder I3. When the ram I4 reaches the end of its forward stroke or when the resistance to itswforward movement overcomes the holding cooperation of the balls 48 with the groove 41 the balls snap out of the groove 41 to release the ram I4 from the ramv I5. When this occurs the spring 80 quickly-moves the ram I4 rearwardly to its rearmost position.v The ram I continues forwardly to `ejecththe charge `of lubricant from the cylinder I3. WThe rearward withdrawal of the turn the ram I 5.

ram I4'from the cylinder- I2 during the forward movement of the ram I5 provides an evacuating action or produces a low pressure in the cylinder I2 so that the lubricant rapidly fills in the cylinder I 2. The'lubricant under atmospheric pressure contained in the body II) and the chamber 26'fully fllls the cylinder I2.

When the forward stroke of the ram I5 is completed the handle I4 is moved rearwardly to re- At the end of the return stroke the groove 4'I comes into cooperation with the balls 48 so that the rams I4 and I5 are reconnected for the succeeding operation. The rearward withdrawal of the ram I5 from the cylinder I3 provides a low pressure in the cylinder I3 and lubricant may flow from the cylinder I2 to the cylinder I3. It is to be observed that the cylinder I2 is opened to the main supply of lubricant under atmospheric pressure at the start or initiation of the active forward stroke of the ram I5 in the cylinder I3. Accordingly the lubricant may fill into the cylinder I2 throughout the active forward stroke of the ram I5 and during the entire return stroke of the ram I5. This allows sufficient time for very heavy lubricant to fully charge the cylinder I2. In the three forms of the invention described above atmospheric pressure acting on the follower F is utilized as a primingforce to fill the cylinder I2 with lubricant.V In each of the forms the manual forward Stroke serves to transfer or displace the charge of lubricant from the priming cylinder I2 to the ejecting cylinder I3 and the directly applied manual force is utilized to positively move the high pressure ram I5 or I5a through the cylinder I3 to eject the lubricant. In each case a full charge of lubricant is supplied to the high pressure cylinder.` I3 ateach operation. The priming cylinder I2 is at least as large in capacity as the ejecting cylinder I3 and the positive displacing action of the ram I4 assures the displacement of a full charge of lubricant from the cylinder I2 to the cylinder I3. -In each form of the invention an ample time inter- Val is allowed for the charging of the cylinder I2 by the action of atmospheric pressure on the lubricant supply. In the form of the invention illustrated in Figs. l to 4, inclusive, the cylinder I2 lls with lubricant during the second or nal stage of the return stroke of the ram I5, inthe form of the invention lshown in Figs. 6 to 9, inclusive, the cylinder I2 is lled with lubricant throughout the return stroke of the ram I 5a, and until the rams I4a and I5a re-enter the cylinder I2, while in the structure illustrated in Figs. 10, 11 and 12 the cylinder I2 may fill with lubricant throughout the time interval required for the forward movement of the ram I5 through the cylinder I3 and for the full return movement of the ram I5 to its initial position.

Having described only typical preferred forms and applications of my invention, I do not wish to be limited or restricted to the specific details herein set forth, but wish to reserve to myself any variations or modifications that may appear to those skilled in the art or fall within the scope of the folowing claims.

Having described my invention, I claim:

l. A grease gun comprising a body having a lubricant reservoir, a charging'cylinder in lubricant receiving relation to the reservoir, and a second cylinder continuing outwardly from the charging cylinder,` a charging ram operable in the charging cylinder, an ejecting ramv operable in the second cylinder, said rams being related for relative longitudinal movement, and releasable means connecting the rams to move as a unit through the charging cylinder to displace a lubricant charge therefrom into the second cylinder an-d releasable to allow continued movement of the ejecting ram in the second cylinder to eject the charge therefrom.

2. A grease gun comprising a body having a lubricant reservoir, a charging cylinder in lubricant receiving `relation to the reservoir, and a second cylinder continuing outwardly from the charging cylinder, a charging ram operable in the charging cylinder, an ejecting ram operable in the second cylinder, the rams being related for relative longitudinal movement,A means for operating the ejecting ram, and latch means releasably connecting the charging ram with the ejecting ram to move therewith during the forward stroke of the ejecting ram so that the rams displace lubricant from the charging cylinder fto the second cylinder, releasable to free the ejecting ram for continued individual movement to eject the lubricant from the second cylinder.

3. A grease gun comprising a body having a lubricant reservoir, a charging cylinder in lubricant receiving .relation to the reservoir and van ejecting cylinder of smaller diameter and greater length than the charging cylinderv and extending forwardly from the charging cylinder in coaxial relation thereto, an ejecting ram adapted to move through the charging cylinder and operate in the ejecting cylinder to eject charges of lubricant therefrom, means for reciprocating the ejecting ram,a charging ram in surrounding relation to the ejecting ram and adapted to operate in the charging cylinder, and releasable means con'- necting the charging ram with the ejecting ram for movement in the charging cylinder to displace lubricant therefrom into the ejecting cylinder during the initial phase of forwardmovement of the ejecting ram and releasable at the completion of said displacement to provide for continued forward movement of the ejecting ram.

4. A grease guncomprising a body having a lubricant reservoir, a charging cylinder in lubricant receiving relation to the reservoir and an ejecting cylinder of smaller diameter and greater length than the charging cylinder and extending forwardly from the charging cylinder in coaxial relation thereto, an ejecting ram adapted to move through the charging cylinder and operate in the ejecting cylinder to eject charges of lubricant therefrom, means for reciprocating the ejecting ram, a charging ram in surrounding relation to the ejecting ram and adapted to operate in the charging cylinder, a movable element in the res-` ervoir engaging the lubricant and exposed to at-l mospheric to feed the lubricant into the charging cylinder, and means for moving the charging ram into the charging cylinder during the forward stroke of the ejecting ram and before the ejecting ram enters the ejecting cylinder to displace a charge of lubricant into the ejecting cylinder, the last named means comprising a detent means for connecting the rams and releasable at the end of the forward stroke of vthe charging ram.

5. A grease gun comprising a body having a lubricant reservoir, a charging cylinder in lubricant receiving relation to the reservoir, and a second cylinder continuing outwardly from the charging cylinder, a charging ram operable in the charging cylinder, an ejecting ram operable in the second cylinder, the rams being relatively shiftable and in telescopic relation, means for reciprocating the ejecting ram, there being a groove in one ram, and a latch part on the other ram cooperable with the groove to caus'e movement of the charging ram with the ejecting ram to eject a charge of lubricant from the charging cylinder to the second cylinder during the forward stroke of the ejecting ram and releasable from the groove to allow the individual continued forward movement of the ejecting ram to eject said charge from the second cylinder.

6. A grease gun comprising a body having a lubricant reservoir, a charging cylinder in lubricant receiving relation to the reservoir, and a second cylinder continuing outwardly from the charging cylinder, a charging ram operable in the charging cylinder, an ejecting ram operable in the second cylinder, the rams being relatively shiftable and in telescopic relation, means for reciprocating the ejecting ram, there being a groove in one ram, a latch part on the other ram cooperable with the groove to cause movement of the charging ram with the ejecting ram to eject a charge of lubricant from the charging cylinder to the second cylinder during the forward stroke of the ejecting ram and releasable from the groove to allow the individual continued forward movement of the ejecting ram to eject said charge from the second cylinder, and means for thereafter re-engaging the latch part in the groove to cause return of the charging ram.

7. A grease gun comprising a body having a lubricant reservoir, a charging cylinder in lubricant receiving relation to the reservoir and an ejecting cylinder of smaller diameter and greater length than the charging cylinder and extending forwardly from the charging cylinder, means for reciprocating the ejecting ram to eject charges of lubricant from the ejecting cylinder, a movable element in the reservoir engaging the lubricant and exposed to atmospheric pressure to feed charges of lubricant into the charging cylinder,

' and ram means for displacing charges of lubricant from the charging cylinder to the ejecting cylinder, said ram means comprising a ram operable in the charging cylinder, and means for connecting the last named ram with the ejecting ram during the rst phase of its forward stroke.

8. A grease gun comprising a body having a lubricant reservoir, a charging cylinder in lubricant receiving relation to the reservoir and an ejecting cylinder of smaller diameter and greater length than the charging cylinder and extending forwardly from the charging cylinder, an ejecting ram operable in the ejecting cylinder, means for reciprocating the ejecting ram to eject charges of lubricant from the ejecting cylinder, a charging ram in shiftable surrounding relation to the ejecting ram and operable in the charging cylinder, there being a groove in the ej ecting ram, and a part on the charging ram cooperating with the groove to cause the charging ram to move forwardly with the ejecting ram to displace lubricant from the charging cylinder to the ejecting cylinder, releasable from the groove when said displacement is complete and re-engaged in the groove during the return stroke of the ejecting ram to return the charging ram.

9. A grease gun comprising a body having a lubricant reservoir, a charging cylinder in lubricant receiving relation to the reservoir and an ejecting cylinder of smaller diameter and greater length than the charging cylinder and extending forwardly from the chargingcylinder, an ejecting ram operable in the ejecting cylindenmeans for reciprocating the ejecting ram to eject charges of lubricant from the ejecting cylinder, a charging ram in shiftable surroundingI relation to the ejecting ram and operable in the charging cylinder, there being a groove in the ejecting ram, a part on the charging ram cooperating with the .groove to cause the charging ram to move forwardly with the ejecting ram to displace'lubricant from the charging cylinder to the ejecting cylinder, releasable from the groove when said displacement is complete, and means for returning the charging ram upon the release of said part to allow recharging of the charging cylinder during the forward stroke of the ejecting ram.

10. A grease gun comprising a body having a lubricant reservoir, a charging cylinder in lubricant receiving relation to the reservoir and an ejecting cylinder of smaller diameter and greater length than the charging cylinder and extending forwardly from the charging cylinder, an ejecting ram Voperable in the ejecting cylinder, means for reciprocating the ejecting ram to eject charges of lubricant from the ejecting cylinder, a charging ram in shiftable surrounding relation to the ejecting ram and operable in the charging cylinder, there being a groove in the ejecting ram, a part on the charging ram cooperating with the groove to cause the charging ram to move forwardly with the ejecting ram to displace lubricant from the charging cylinder to the ejecting cylinder, releasable from the groove when said displacement is complete, and means for returning the charging ram upon the release of said part to allow recharging of the charging cylinder during the forward stroke of the ejecting ram, the last named means includlinga return spring connected with the charging ram.

ll. A grease gun comprising a body having a lubricant reservoir, a charging cylinder in lubricant receiving relation to the reservoir, and a second cylinder continuing outwardly from the charging cylinder, a charging ram operable in the charging cylinder, an ejecting ram operable in the second cylinder, means for reciprocating the ejecting ram, and releasable means connecting the charging ram with the ejecting ram to move ltherewith during the rst phase of its forward stroke to displace lubricant from the charging cylinder into the second cylinder and releasable when said displacement is complete and operable to reconnect the charging ram with the ejecting ram during .the first phase of return movement of the ejecting ram to restore the charging ram.

12. A grease gun comprising a body having a lubricant reservoir, a charging cylinder in lubricant receiving relation to the reservoir and an ejecting cylinder of smaller diameter and greater length than the charging cylinder and extending forwardly from the charging cylinder, an ejecting ram operable in the ejecting cylinder, means for reciprocating the ejecting ram to eject charges 4of lubricant from the ejecting cylinder, a charging ram in shiftable surrounding relation to the ejecting ram and operable in the charging cylinder, there being a groove in the ejecting ram, and a part on the charging ram cooperating with the groove .to cause the charging ram `to move forwardly with the ejecting ram to displace lubricant from the charging cylinder to the ejecting cylinder during the first phase of the forward stroke, there bei-ng a second groove in the ejecting ram releasably engaged by said part to return the groove in one ram, and spring pressed balls on the other ram cooperable with the groove to cause movement of the charging ram with the ejecting ram to eject a charge of lubricant from the charging cylinder to the second cylinder during the forward stroke of the ejecting ram and releasable from the groove to allow the individualcontnued forward movement of the ejecting ram to eject said charge from the second cylinder.

NEIL V. SMITH. 10 

